A simulation Study on the System Combined Solar Energy with Biogas Boiler for Floor Radiant Heating and Fuel

A mathematical model was built for simulating an innovative design system combined solar energy with biogas boiler for floor radiant heating and fuel. Effects of the ambient air temperature on the performance of the system had been examined. And the results also support theoretical feasibility of the system.

Experimental study of low-temperature electrical radiant floor heating system

To evaluate the thermal performance of a low-temperature electrical radiant floor heating system,an experimental facility equipped with a constant temperature chamber and different specimen floors is designed and built.The heating cable is installed in the floor slab with a unit-rated power of 30 W/m.Twenty-four different schemes are worked out and tested,which include three kinds of composite floor structures and eight kinds of cable distances.The cable distances are 30,40,50,60,80,100,130,150 mm.The main affective factors of the thermal performance and their influencing regularity are discussed.The experimental results show that the system has good stability and reliability,and the ratio of the radiation heat-transfer rate to the gross heat-transfer rate is greater than 50%.When the floor structure and the cable distance are fixed,the gross heat-transfer rate of the upper floor surface has a maximum value at an optimal cable distance.Under the experimental conditions in this paper,the optimal cable distance is 50 mm.

Feasibility Analysis on the Integrated Application of Solar Energy, Biogas, Coal-fired Boiler and Radiant Floor Heating for Rural Residence

The feasibility of adopting a balanced energy mix mode (domestic solar energy, biogas, coal-fired boiler and radiant floor heating) was proposed. Taking a typical rural residence in Zhengzhou City for example, the study through theoretical analysis and calculation showed that such a balanced energy mix is an economic way and efficient in saving energy and reducing air pollution, and elaborated the theoretical feasibility of popularizing such a heat supply mode in rural areas.

Experimental investigation on heat transfer characteristics of a new radiant floor system with phase change material

In order to improve the heat transfer characteristics of the traditional phase change material（PCM） floor, a new double-layer radiant floor system with PCM is proposed, which can store thermal or cold energy in the off-peak period and use them in the peak period. An experimental setup was developed to study the heat transfer characteristics of the new system under both cooling and heating modes. The experimental results show that the double-layer radiant floor system with PCM can meet both the cold and thermal requirements of users. Moreover, with the same duration of the thermal energy storage process, the increase of water temperature supplied to the system can improve the heat transfer characteristics of the system but lead to the discomfort of users. On the other hand, if the air temperature at the end of the thermal energy storage process is the same under different conditions, the increase of supplied water temperature will decrease the thermal energy storage time and ensure the comfort of users.

Environmental load of solid wood floor production from larch grown at different planting densities based on a life cycle assessment

As one of the main structural units in a building,a solid wood floor has significant strategic research value for low-carbon energy saving.Taking the production line of a solid larch wood floor as a case study,we assessed the environmental load during production based upon a life cycle assessment.Using GaBi 6.0 software,we analyzed the associated carbon sequestration during floor production,with the initial planting density serving as the disturbance factor in a modular analysis.The results indicated that the cutting and finishing steps have relatively intense,negative influences on the environment,whereas transportation,ripping,and trimming do not.Additionally,recycling biomass waste has the potential to reduce greenhouse gas emissions.When the initial planting density was 3.0×3.0 m,carbon sequestration was relatively high.Although the emissions of freshwater pollutants,volatile organic compounds,and fine particulate matter（matter with a 2.5-μm diameter） were comparatively high,the reduction of greenhouse gas emissions was still excellent at this planting density.

On the optimisation of age of the air in the breathing zone of floor heating systems:The role of ventilation design

For a mechanically ventilated space,the nominal age of the air can be obtained by the reciprocal of the air change rate.However,values of the local mean age of the air in practice may differ to some extent from the nominal one since the nominal time constant employs as reference the theoretical optimum model.This discrepancy could become more prominent in spaces conditioning with both ventilation and heating system where the indoor air pattern is affected by turbulent mixed convection flow.Given importance of knowledge on the distribution of age of the air in these spaces,the present study provides insights on how ventilation design in floor heating systems can optimise the delivery of fresh air into the breathing zone.In this context,by establishing a computational fluid dynamic(CFD)model validated against experimental data,the local mean age of the air as well as the indoor air quality(IAQ)indices in the breathing zone of the floor heating system are examined under different ventilation modes.Six different ventilation scenarios are regarded in order to find the optimal ventilation design in terms of the delivery of the fresh air and ventilation effectiveness in occupied space.Furthermore,the integrated effects of the floor temperature and inlet supply temperature along with the ventilation design on the distribution of local age of the air are addressed.The obtained results indicate that the up-supply ventilation strategy is more efficient than down-supply one in the ventilation effectiveness and delivery of fresh air into the breathing zone.Moreover,it is shown that the mean age of the air in the breathing zone of the up-supply ventilation increases with increment of the Ri(Richardson number),whereas an increase in Ri improves the delivery of fresh air in down-supply mode.For a given floor temperature,the similar trend is also observed in the variation of age of the air with the characteristic temperature of supply inlet,namely the temperature difference between inlet supply and surrounding walls.

Quantitative &Qualitative Regulation of Peripheral Leukocyte Subsets plus Emotional Hormones by Floor Heating

A floor heating system is a traditionary famous in Asian countries, especially in North East of China and Korea. In this report, we intended to clarify the effect of floor hating system for accessing a peripheral leukocyte regulation in winter season by evidence-based manner more than VAS. We set up two different office rooms heat-controlled by floor heating and air-conditioned by ceiling electric heater. Both qualitative and quantitative approaches determine which are better therapeutic effective recipes for this trial. The elements were evaluated by the total number of peripheral leukocyte, granulocyte and lymphocyte ratio and lymphocyte subsets. For 5 days of working in each conditioned room, the volunteers were changed the room after one-week interval for cooling down. Floor heating system regulated total number of peripheral leukocyte. The mode of the action for the high number of the volunteer was down-regulated. On the contrary, in lower numbers it was up-regulated after the trial. The number of leukocyte subsets, granulocyte and lymphocyte were also regulated by dose dependent manner. Emotional hormone, adrenalin, cortisone and nor-adrenaline were down regulated by floor heating but dopamine was up-regulated by this heating system. The reversal results were obtained by the group who worked in the conditioned room by the system heating from ceiling.

Refrigerator Coupling to a Water-Heater and Heating Floor to Save Energy and to Reduce Carbon Emissions

With an aim of rationing use of energy, energy safety, and to reduce carbon emission, our interest was geared towards the refrigerators and all the refrigerating machines. Indeed the heat yielded by the exchanger condenser can be developed for the water heating, floors heating etc. After an encouraging theoretical study, two prototypes were produced in order to validate the theoretical results. A first refrigerator was coupled with a water-heater and another with a heating floor. The water temperature reached, in one day, is of 60℃;which makes it possible to predict better results with a continuously used refrigerator. In the same way for the heating floor coupled with the second refrigerator, the temperature reached high values because the surface is reduced;however for the heating floors the standard fixes the temperature between 28℃ and 30℃.

Evaluation of the thermal performance of radiant floor heating system with the influence of unevenly distributed solar radiation based on the theory of discretization

In the building with many transparent envelopes,solar radiation can irradiate on the local surface of floor and cause overheating.The local thermal comfort in the room will be dissatisfactory and the thermal performance of radiant floor will be strongly affected.However,in many current calculation models,solar radiation on the floor surface is assumed to be uniformly distributed,resulting in the inaccurate evaluation of the thermal performance of the radiant floor.In this paper,a calculation model based on the theory of discretization and the RC thermal network is proposed to calculate the dynamic thermal performance of radiant floor with the consideration of unevenly distributed solar radiation.Then,the discretization model is experimentally validated and is used to simulate a radiant floor heating system of an office room in Lhasa.It is found that with the unevenly distributed solar radiation,the maximum surface temperature near the south exterior window can reach up to 35.6℃,which exceeds the comfort temperature limit and is nearly 8.5℃higher than that in the north zone.Meanwhile,the heating capacity of the radiant floor in the irradiated zone can reach up to 171 W/m^(2),while that in the shaded zone is only 79 W/m^(2).The model with the assumption of uniformly distributed solar radiation ignores the differences between the south and north zones and fails to describe local overheating in the irradiated zones.By contrast,the discretization model can more accurately evaluate the thermal performance of radiant floor with the influence of real solar radiation.Based on this discretization model,novel design and control schemes of radiant floor heating system can be proposed to alleviate local overheating and reduce heating capacity in the irradiated zone.

Comparative Study of Two Carbon Fiber Cathodes and Theoretical Analysis in Microbial Fuel Cells on Ocean Floor

Cathode activity plays an important role in the improvement of the microbial fuel cells on ocean floor （BMFCs）. A comparison study between Rayon-based （CF-R） and PAN-based carbon fiber （CF-P） cathodes is conducted in the paper. The two carbon fibers were heat treated to improve cell performance （CF-R-H ＆ CF-P-H）, and were used to build a new BMFCs structure with a foamy carbon anode. The maximum power density was 112.4mWm-2 for CF-R-H, followed by 66.6mWm-2 for CF-R, 49.7 mWm-2 for CF-P-H and 21.6mWm-2 for CF-P respectively. The higher specific area and deep groove make CF-R have a better power output than with CF-P. Meanwhile, heat treatment of carbon fiber can improve cell power, nearly two-fold higher than heat treatment of plain fiber. This improvement may be due to the quinones group formation to accelerate the reduction of oxygen and electron transfer on the fiber surface in the three phase boundary after heat treatment. Compared to PAN-based carbon fiber, Rayon-based carbon fiber would be preferentially selected as cathode in novel BMFCs design due to its high surface area, low cost and higher power. The comparison research is significant for cathode material selection and cell design.

Simulation Analysis on Mass Concrete Temperature Field of Lock Floor Layered Pouring

Based on the background of navigation lock structure engineering in Changsha Integrated Hub, this study used Parametric Design Language （APDL） compilation command on the t＇mite element program ANSAYS platforms to simulate the temperature field of the layered pouring process about the lower lock head. The temperature contour map and the change laws of temperature field with time in each different levels of the floor were obtained. And compared with the actual instrument measurement data, the feasibility of the simulation analysis was concluded. Then, this study optimized the pouring process, obtained the suitable methods of layered pouring and put forward the measures to reduce the concrete temperature crack.

Consumption and species preference for house construction wood in central highlands of Ethiopia–implications for enhancing tree growing

A study was conducted in central Ethiopian highland in 2008 to investigate the consumption of house construction wood, the tree species preference for construction wood and the forthcoming conditions of this forest product and possible strategies for future availability. Twenty-four iron-roofed houses and twenty-eight thatch-roofed houses belonging to thirty-six farm households were investigated for types, volumes and sources of construction wood used. It was found that an average farmhouse with a floor space of 57 m^2 consumed about 13.7 m^3 of wood. Both floor space and wood consumptions vary with house types An average iron-roofed house with floor space of 51.9 m^2 consumed 16.8 m^3 of wood and an average thatch-roofed house with mean floor space of 28.6 m^2 consumed 3.2 m^3 of wood. Family size and floor space were the major factors influencing construction wood consumption. An average living house was composed of woods of 39.3% ,luniperus procera, 5.6% Cupressus lusitanica, 29.2% Eucalyptus globulus and 26% Eucalyptus camaldulensis. The wood volume from the first two species and half that of the third species were obtained from state forest which is currently banned from any construction wood extraction and hence there is a shortage of around 59.5% of woods. We suggest the promotion of various tree planting approaches to increase the wood supply and the use of alternative local materials like soil bricks for house construction.

Crawlspace heating system in detached house with insulated foundation

Two practical crawlspace heating systems introduced in detached houses have been chosen as a field study. One is the crawlspace warm air heating system and the other is the crawlspace hot water circulation system. Based on the field study result, by using the simulation sol, ware, THERB, the effectiveness of the crawlspace warm air heating system has been examined. The effect of the factors, such as the wind amount circulating between crawlspace and indoor space, foundation insulation condition, and heat amount into the crawlspace, on the indoor thermal environment has been analyzed. Based on these analyses, the measured crawlspace heating system can make the average temperature of the living room above 20℃. These two houses have excellent thermal environment. According to the simulating result, heat amount input into crawlspace, which can make comfortable indoor thermal environment, for every month in heating period has been roughly concluded, and they are 600 W in December and March and 800 W in February and January, respectively.

国家标准GB/T 18103—2022《实木复合地板》解读

国家标准GB/T 18103—2022《实木复合地板》已于2022年12月30发布,2023年7月1日实施。简述标准修订过程、修订原则和内容变化,通过对标准术语和定义、分类、要求、检验方法、检验规则以及标识、包装、运输和贮存等的解读,引导标准的正确理解和实施应用。

新疆克州地区学校建筑供暖系统设计研究

研究了新疆克州地区某中学供暖系统设计的思路和流程,包括热源的选择、供暖系统设计,换热站设计等,深入探讨和分析了调试过程中出现的问题,对设计和施工阶段需要关注的设计调研、施工规范等关键环节进行了总结与反思,并提出了解决方案。

2023年中国木塑地板、石木塑地板等出口情况及贸易壁垒分析

依据中国海关数据,分析2023年中国木塑地板、石木塑地板等地板产品出口数量、出口金额、出口市场以及中国出口省份等情况,阐述了木塑地板、石木塑地板等出口涉及的贸易壁垒。2023年中国出口石木塑地板、PVC卷材地板和LVT地板等含PVC聚合物的地板产品为460.01万t,同比2022年降低9.20%;出口户外用木塑地板等含PP、PE等聚合物的地板产品58.49万t,出口量略有下降,但基本稳定。北美洲国家是该产品的主要出口市场,且占比较高;江苏省和浙江省是中国生产和出口大省。中国木塑地板和石木塑地板出口主要受美国“337调查”和“301条款”贸易壁垒影响。

龙骨结构对体育木地板的冲击吸收率性能研究

为了深入研究龙骨结构参数对体育木地板冲击性能的影响,对不同龙骨结构、材料的体育木地板进行冲击吸收率比对分析。结果表明:体育木地板的结构对冲击吸收率有显著影响,龙骨结构的差异会导致冲击吸收率的变化,冲击点位因龙骨位置影响体育木地板的冲击吸收率。实木龙骨结构的体育木地板冲击吸收率普遍优于LVL龙骨结构。单层实木龙骨和单层LVL龙骨的平均冲击吸收率分别为56.1%和54.9%,双层实木龙骨和双层LVL龙骨的平均冲击吸收率分别为55.3%和54.4%。体育木地板龙骨上的冲击点位低于无龙骨位置的冲击点位,双层龙骨体育木地板的龙骨交叉冲击点位的冲击吸收率最低,对双层龙骨结构的冲击吸收率整体结果影响较大,龙骨结构是影响体育木地板冲击吸收率的关键因素之一。

内埋可变导热管建筑顶面隔热层节能分析

为减少室内空调能耗,文中对目前广泛使用的在建筑顶面之上铺制隔热层的建筑节能方法做进一步优化。文中以北京地区某建筑为例进行计算分析发现,隔热层的高热阻在夜间不利于建筑顶层白天积累的热量向外界排散。为在夏季夜间减小隔热层热阻,加速建筑顶层白天积累热量的排散,提出一种内埋可变导热管的建筑顶面隔热层,即在建筑顶面隔热层内间隔一定距离埋制可变导热管。夏季白天工况,可变导热管不启动,为高热阻状态;夏季夜间工况,可变导热管传热能力强,减小了隔热层热阻,加快了夜间建筑顶层结构热量的向外排散,计算结果表明,按照间隔0.3m铺制可变导热管的隔热层比铺制普通隔热层的空调制冷量下降15.1%;冬季工况热管传热能力非常差,隔热层保持了高热阻状态,避免了室内热量损耗。这种方法节能效果明显,可为建筑节能研究工作提供参考。

中国木地板产业发展现状及对策建议

2019年我国木地板产量达到阶段性历史峰值,木地板产业进入高质量发展阶段。当前产业发展形势严峻:企业效益普遍下滑;国内市场存在“逆向选择”现象;国际市场频繁遭遇贸易壁垒;科技创新增效显示度不高;制造和服务模式面临挑战。本文在对上述发展现状和问题深入分析后,借鉴产业数字化、融合式发展等传统产业转型升级路径理论,提出木地板产业高质量发展的对策建议:一是锚定国内大循环,实施需求驱动木地板产业与服务业深度融合。建议首要任务是致力于满足客户的需求,从产品导向向满足用户体验转变,实施需求驱动,将“能够让消费者在使用产品或享受服务中得到满足”作为衡量企业转型升级成功的标准。二是提升自主创新能力,实施创新驱动木地板产业与研发端深度融合。建议加强跨企业技术流动,大企业发挥主导和引领作用,中小企业向“专精特新”方向发展,协同促进生产力跃迁,逐步构筑新竞争优势,赢得发展的主动权。三是发扬工匠精神,努力提高产品质量和服务质量。建议从产品设计、工艺、原材料、销售服务、铺装服务、品牌创建等全过程下苦功,致力于提升用户体验。四是有组织地开展科学普及,努力消除与消费者间的信息不对称。建议组织开展地板相关知识的科普工作,努力消除信息不对称,避免逆向选择,引导消费者正确认知、科学消费、绿色消费。

空气源热泵直接地板辐射供暖升温过程实验研究

空气源热泵直接地板辐射供暖系统以制冷剂为热媒直接加热地板,具有系统简单、传热效果好的优点。文中搭建空气源热泵直接地板辐射供暖实验装置,在0℃、-5℃和-10℃3种不同室外环境温度下,对毛细管地板辐射末端供暖升温过程进行实验研究。实验结果表明:室外温度为-5℃时,地板温度稳定基本需要120 min,同一根毛细管壁制冷剂蒸气入口端与出口端温差较小为1.55℃,而在20 mm厚水泥地板表面上其温差为1.73℃;室外温度为-10℃时,地板升温速度最慢为0.15℃/min,小室内空气升温速度为0.09℃/min,此时机组制热COP稳定在3.06。